President George W Bush has urged America's Nato allies to remain involved in Iraq.

Speaking at the G8 summit in Georgia, with his staunch ally, UK Prime Minister Tony Blair at his side, the president's remarks appear to be a call for a greater Nato role in security operations in Iraq.

But it is hard to see how eager Nato would be to take on such an additional responsibility.

Some 15 Nato countries have already sent troops to Iraq and Washington's closest Nato ally, Britain, is considering despatching additional units if required.

But the involvement of soldiers from Nato countries is very different from an involvement by Nato as a military alliance.

Mission too far?

There has certainly been talk in some quarters about a potential Nato role; nothing would please Washington more.

But many Nato members are wary. The German government for one has spoken out against the alliance becoming involved.

And the French President, Jacques Chirac, has quickly responded to Mr Bush's comments by indicating that he does not believe that it is Nato's job to intervene in Iraq.

For many alliance members this would be a mission too far. Nato is in the process of expanding its operations in Afghanistan beyond the capital, Kabul.

It has struggled for months to find countries willing to despatch key capabilities - a handful of transport helicopters for example - and it is by no means clear that generating additional forces for Iraq would be politically or practically feasible.

More British troops could come from a major Nato unit - the Allied Rapid Reaction Corps based in Germany. But if sent they would be going under a British rather than a Nato banner.

Nato has had a limited role in helping to plan the deployment of troops from one of its newest members, Poland, to Iraq.

In the future such back-room help might be forthcoming but the deployment of a Nato force to Iraq seems to be out of the question.